Spirit-level



(No Model.)

P. L. FOX. SPIRIT LEVEL.

No. 436,495. Patented Sept. 16, 18901.

W1 TJVESSES keum (M7 dem.

UNITED STATES PATENT OFFICE.

Fruto L. FOX, oF BRIDGEPORT, CONNECTICUT.

SPIRIT-LEVEL.

SPECIFICATION forming part of Letters Patent No. 436,495, datedSeptember 1,6, 1890.

Application filed May 12, 1890. Serial Ilo. 351,410. (No model.)

T0 all whom it may concern.-

Beit known that I, PHILO L. FOX, a citizen of the United States,residing atBridgeport, in the county of Fairfield and State ofConnecticut, haveinvented certain new anduseful Improvements in Plumbsand Levels; and I do hereby declare the following to be a full, clear,and exact description of the invention, such as will enable othersskilled in the art to which it appertains to make and use the same.

My invention relates to plumbs and levels generally, and has for itsobject to greatly improve their construction and mode of operation, toproduce, in brief, an instrument of the very finest quality in which thecost of production shall be diminished rather than increased. l

With these ends in View I have devised the simple and novel constructionwhich I will now describe, referring by numbers to the accompanyingdrawings, forming part of this specification, in which Figure 1 is anelevation of my novel plumb and level; Fig. 2, a central longitudinalsection, and Fig. 3 a cent-ral transverse section thereof.

In my improved plumb and level, instead of a heavy strip of wood intowhich the spiritvials are recessed, or a metal plate to which they areattached, I form the body of the instrument of two comparatively lightstrips of wood, which are rigidly secured together by metalliccross-pieces. This construction I have found greatly superior inpractice, as it practically does away withthe trouble of the bodieswarping, which has been a serious obj ection to instruments of thisclass in which the bodies were made of wood, and, furthermore, itenables me to so arrange the vial of the level as to permit the floatingair-space to be visible from below when the instrument is used above thehead-as in leveling the top of a door-and to so arrange the vial of theplumb that the air-space will be visible from every point of view whenthe instrument is in a perpendicular position. Heretofore withinstruments of this class it has been necessary for the operator toplace himself high enough to enable him to look down upon the air-spacein using either the plumb or level.

1 denotes strips of wood which are beveled inward upon their innersides, as at 2. These strips are of course made of well-seasoned hardwood, and I secure them together by screws 3, which pass entirelythrough the strips and engage solid metallic cross-pieces 4, as clearlyshown in Fig. 2.

5 denotes the spirit-vials, which are of ordinary construction.

A denotes plu mbs, and B a level. The plumbs lie transversely betweenthe strips.

In order to protect the spirit-vials of the plumbs and secure themagainst breakage under all ordinary circumstances and at the same timepermitthe floating air-spaces to bevisible from all directions whentheinstrument is held perpendicular, I inclose the spirit-vials intransparent tubes 6, there being preferably a slight air-spacesurrounding the spiritvial and between it and the tube. The tubes andvials may of course be secured in position in any suitable manner. Ipreferably, however, make transverse openings 7 through the strips, ofjust sufficient size to receive the transparent tubes closely and plugup the ends of the openings, taking care to iiX the vials centrally inthe tubes.

In practice I ordinarily plug up the ends of the openings with putty orplaster, as indicated at 8, although any other suitable plastic materialmay be used, if preferred, and cover the openings with metallic caps 9.I place the spirit-vial of the level in a similar transparent tube andplug up the ends thereof with putty or other plastic substance in thesame manner as the vials of the plumbs. The tube and vial are placed ina recess 10 in the outer face of one of the strips, and the recess iscovered by a plate 11, which is secured to the strip by screws or in anysuitable manner.

In order that the floating air-space of the level may be seen frombelow,I form slots 12 in the under sides of the strips, said slotsextending from bevels 2 into recess l0, as is clearly shown in Figs. land 3. These slots canse the floating air-space to be visible, when thelevel is horizontal, from below and on both sides. This is an importantfeature of construction, as it renders itwholly unnecessary for theoperator to get upon some object high enough to enable him to look downupon the air-space.

The use of the transparent tubes in the plumbs is likewise a veryvaluable feature of IOO my invention, as it enables me to use aconstruction in which the air-spaces are visible from all directionswhen the instrument is perpendicular. It will of course be apparent thatthe same result would be accomplished by using metallic tubes providedwith longitudinal slots. This, however, is such an obvious modificationthat it is not deemed to require illustration, and, furthermore, l findthe transparent tubes greatly superior in practice.

Having thus described my invention, I claiml. A plumb and levelconsisting of two strips of wood, cross-pieces connecting said strips,one or more spirit-vials recessed in the strips,

and one or more spirit-vials inclosed in transparent tubes and placedtransversely between the strips.

2. In an instrument of the class described, two strips connected bycross-pieces, and lying between said strips one or more spirit-vials1nclosed in transparent tubes, as and for the purpose set forth.

In testimony whereof I aix my signaturein presence of two witnesses.

PHIL() L. FOX.

Witnesses:

A. M. WoosTER, ARLEY I. MUNsoN.

